Damon is an opportunist in Syracuse (Sicily) where Dionysius is a tyrant whose enforcer Cariso has been charged with finding the (Greek) foreigner named Arcanos who’s been teaching disruptive Pythagorean ideas like “everyone is equal” and “killing others is wrong”. Damon finds a way to profit from each and Arcanos is forced into hiding. When the leader of Greece dies Pythias is convinced by the council that despite the fact that his wife is pregnant he is the only one that can go to Syracuse to retrieve Arcanos who is to be the next leader. Nerissa is enraged and later even suicidal.

Damon quickly recognizes the foreign Pythias as an easy mark but later helps him to escape from Cariso as well. The two hide out in Adriana’s rooftop hovel. Damon helps Pythias get in touch with some of the Greek teacher’s students who can help them find Arcanos but Damon isn’t trusted. Insulted he decides to assist Cariso in order to obtain a valuable horse. Once Adriana lets slip that Damon has been seen riding the new stallion Pythias no longer trusts Damon either and after a fight in which he chooses not to kill Damon – a gesture that changes the opportunist Pythias leaves to find Arcanos on his own.

Cariso’s men surreptitiously follow Pythias but so does Damon who slows down Pythias’ pursuers then joins he and Arcanos helping them to escape. But Pythias dressed as Arcanos is captured while the Greek teacher escapes to his homeland. Damon then offers his life for his friend’s and Dionysius allows it in order that Pythias may return to Greece to attend to his sick pregnant wife. However in the bargain Pythias must return within 2 months else Damon will be put to death. While Cariso questions his tyrant’s logic Dionysius sees this as an opportunity to kill the dangerous ideas spread by Arcanos.

Pythias returns to Greece helping to pull Nerissa out of her ill health and enabling her to give birth to their son which they name Damon. But Nerissa isn’t happy when Pythias tells her that he must return to save Damon’s life in exchange for his own. Nevertheless he leaves for Syracuse where Dionysius had instructed Cariso to prevent Pythias’ return. But of course Pythias eventually makes his way to the city center just as Damon is about to be executed on his behalf. Then only an intervention by the tyrant’s own son saves the two … and presumably the ideas live on to destroy his (and/or his predecessor’s) rule.